U.S. Pat. No. 4,009,668 to Brass et al shows a planting apparatus which has had considerable commercial success. In general, planters of this type have a furrow forming mechanism, a mechanism for depositing seeds at spaced intervals in such furrow and a furrow closing mechanism whereby the seeds are covered by soil and are thereby ready to grow.
A wide variety of seed furrow closing systems are used on planter row units. The primary function of such systems is to cover the planted seed with soil and provide good seed-to-soil contact for optimum seed germination. With a minimum amount of adjustment, they are required to work in a wide range of soil conditions. They must also work well at different planting depths.
In light or moist soil, or planting shallow, a narrow closing system, one with the soil moving components close to the centerline of the row, would function better than a wider one. A narrow system would move less soil toward the seed, thereby better maintaining the intended seed depth by not moving excessive amounts of soil on top of the seed. Also, a system that moves less soil has a much smaller chance of moving the seed from its intended position.
In the aforementioned commercial embodiment of the Brass et al patent, provision was made for adjusting the depth of the furrow made in the soil. When the depth of the furrow is increased, because it is a V-shaped furrow, the top of the furrow will become wider. Conversely, if the furrow is made shallower, the distance across the top of the furrow will decrease. However, in such commercial embodiment of the Brass et al patent, no provision was made for adjusting the distance between the furrow closing wheels. Ideally, the distance between the furrow closing wheels where they contact the soil adjacent each side of the top of the furrow should be adjusted depending upon the actual width of the top of the furrow. But heretofore there has been no solution to such problems. Consequently, there exists a need for an apparatus to solve such problems.